TM 5-4320-306-10
2-6. OPERATING PROCEDURE (Continued)
(9) The check valve on the discharge manifold assembly is forced open when discharge pressure indicated
on PUMP DISCHARGE GAGE (12) is high enough to initiate flow.
CAUTION
After centrifugal pump unit is primed and pumping, maintain engine idle speed until engine
warmup cycle is complete.
(10) Run the centrifugal pump unit with engine at idle speed for a few minutes. Adjust MANUAL
THROTTLE CONTROL knob (10) until desired operating speed is reached. Refer to paragraph g.
(11) Partially close the discharge gate valve
(1) to fill the hose slowly and guard against excessive
shock pressure to fittings. As the discharge hose fills, open
the discharge gate valve until it is adjusted to the required
discharge flow rate.
CAUTION
Impeller cavitation occurs when engine speed is increased beyond the point of maximum suction
vacuum. Cavitation is harmful to the pump unit and should be avoided at all times. Cavitation is
indicated by a very loud cracking noise in the pump housing.
NOTE
Engine speed and pump discharge will vary in accordance with the output demand. When there is
no increase in vacuum (suction) as indicated on the suction gage, maximum pumping capacity
has been reached.
g. Adjustments. Engine speed and pump discharge pressure are controlled with MANUAL THROTTLE
CONTROL knob (1). Pull MANUAL THROTTLE CONTROL knob out to increase engine speed and pump discharge
pressure; push in to decrease engine speed and pump discharge pressure. Adjust the MANUAL THROTTLE CONTROL
until the required speed and discharge pressure are
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